1. Field of the Invention
The present invention relates to a magnetic memory device, and particularly relates to a magnetic memory device having a tunneling magneto-resistance element.
2. Description of the Related Art
In the magnetic memory device of the prior art, the tunneling magneto-resistance element (hereinafter referred to as “TMR element”) is used as a memory cell. However, in the conventional TMR element, since a shape of the memory cell is formed in a rectangular plane, an irregular magnetic domain occurs in a periphery of the rectangular plane and a magneto-resistance ratio (MR ratio) is decreased.
A long side of the TMR element is formed so as to be particularly larger than a short side and a direction of the long side of the TMR element is formed so as to be parallel to a magnetization direction, in order that an effect of demagnetizing field is avoided to suppress the occurrence of the irregular magnetic domain and the MR ratio is improved. Consequently, miniaturization of the magnetic memory device is prevented.